Self-adjusting spherical bearing assembly

ABSTRACT

A spherical bearing assembly having an inner race member and an outer race member, the inner surface of the outer race member being a concave spherical surface, the outer surface of the inner member being a complimentary convex spherical surface, the inner member including a spool member having an annular groove disposed on its outer surface and at least three sperical segments, each segment having a groove on its inner surface complimentary to said annular rib, said segments disposed on and interlocked with said spool member by the registration of said annular rib in said complimentary annular groove.

United States Patent [191 McCloskey SELF-ADJUSTING SPHERICAL BEARINGASSEMBLY [75] Inventor: Albert R. McCloskey, Fairfield,

Conn.

[73] Assignee: Rockwell International Corporation,

Pittsburgh, Pa.

22 Filed: Jan.25, 1974.

21 Appl. No.: 436,546

[52] US. Cl 308/72; 308/238 [51] Int. Cl. F16C 9/06; F16C 11/06;

F16C 23/08; F16C 27/04 [58] Field of Search 29/1484, 149.5; 308/72,308/238 [56] References Cited UNITED STATES PATENTS 2,675,283 4/1954Thompson 308/238 1 Oct. 28, 1975 Barr 29/148.4

Abel 308/72 Primary Examiner-M. Henson Wood, Jr. AssistantExaminerl-loward Beltran [57] ABSTRACT A spherical bearing assemblyhaving an inner race member and an outer race member, the inner surfaceof the outer race member being a concave spherical surface, the outersurface of the inner member being a complimentary convex sphericalsurface, the inner member including a spool member having an annulargroove disposed on its outer surface and at least three spericalsegments, each segment having a groove on its inner surfacecomplimentary to said annular rib, said segments disposed on andinterlocked with said spool member by the registration of said annularrib in said complimentary annular groove.

3 Claims, 13 Drawing Figures US. Patent Oct. 28, 1975 Sheet10f23,915,518

Sheet 2 0f 2 US. Patent Oct. 28, 1975 SELF-ADJUSTING SPHERICAL BEARINGASSEMBLY BACKGROUND OF THE INVENTION The present invention relatesgenerally to selfaligning bearings having a balllike inner member with aconvex outer surface and an outer member having an inner surface with acomplimentary concave spherical inner face. These types of bearings,which are commonly called spherical bearings, have been utilized inindustry for a substantial period of time. The technological evolutionof these type bearings has been directed more in the terms of materialcomposition of its various component parts rather than toward basicchanges in design concepts. Accordingly, the design advances inspherical bearings have not been substantial in nature and therebypresently limiting their applications.

One area in which the spherical bearings have been extensively appliedis the aircraft industry. This is due to the spherical bearingself-aligning characteristic. A typical such application is marrying ofa spherical bearing to a landing gear strut or member of an airplane. Inthis application the outer race is commonly press-fitted and/or stakedinto a housing or the like rendering it difficult to remove and/ormaintain. When any such maintenance is required, such as replacing ofthe ball, the entire bearing assembly including the inner and outer racemember would have to be removed and replaced by an entirely new bearingassembly. Such an operation could entail substantial expense and downtime of the entire aircraft.

There are a number of prior art type spherical bearings which have beenaddressed to this kind of problem. One such type prior art bearing isthe messerschmidt" bearing. A concept of this bearing is that the ballcan be removed in the field without disassembling the entire bearing,that is, removing the outer race member from its mounting. Themessersclimidt type spherical hearing has proved somewhat unsatisfactoryin that its overall bearing surface is decreased by the provision ofaslot. This decrease or rather limited bearing surface area has a markednegative effect on the bearing performance characteristics.

SUMMARY OF THE INVENTION It is therefore, a primary object of thepresent inven tion to provide a spherical bearing assembly having aninner race member and an outer race member, the inner surface of theouter race member being'a concave spherical surface, the'outer surfaceof the inner member being a complimentary convex spherical surface, saidinner member including a spool member and at least three sphericalsegments interlocked, "in an axial direction, with said spool member.

It is yet another object of the present invention to provide a sphericalbearing assembly which hasa rotational redundancy. That is, the innermember is adapted to be rotatably mounted within the outer member. Afirst bearing surface between these two members being defined by theconvex outer surface of the inner member and the complimentary concaveinner surface of the outer member. The rotational redundancy provided bythe spherical bearing of the present invention is the second bearingsurface between the longitudinal inner surface of the segments of theinner member and the cylindrical outer surface of the spool member.

It is still another object of the present invention to provide aspherical bearing assembly in accordance with the present inventionwherein the spool member is provided with an annular rib disposed on itsouter surface and at least three spherical segments, each segment havinga groove on its inner surface complimentary to the annular rib on thespool member, the spherical segments disposed on and interlocked withthe spool member by the registration of the annular rib in thecomplimentary annular groove.

It is'still another object of the present invention to provide aspherical bearing assembly in accordance with the present inventionwherein the annular rib is centrally disposed on the outer surface ofthe spool member.

It is yet another object of the present invention to provide a sphericalbearing assembly in accordance with the present invention wherein theregistration of the rib within the groove maintains the segments uponthe spool member so as to mechanically interlock them thereon when themember is in its operational position.

It is still another object of the present invention to provide aspherical bearing assembly in which the grooves formed on the innersurface of the spherical segments are in line and form a continuousannular groove which is adapted to receive the annular rib disposed onthe outer surface of the spool member.

It is still another object of the present invention to provide aspherical bearing assembly in which there are three spherical segments,the segments providing substantially all of a first bearing surfacebetween the inner member and the outer member.

It is still another object of the present invention to I provide aspherical bearing assembly in which the concave inner surface is coatedwith a self-lubricating plastic such a Teflon, a trademark of the DuPontCorporation.

It is yet another object of the present invention to provide a sphericalbearing assembly in which the outer surface of the spool member iscoated with a selflubricating plastic material such as Teflon.

It is yet another object of the present invention to provide a sphericalbearing assembly in which the outer surface of said inner member asdefined by the spherical segments are coated with self-lubricatingplastic such as Teflon.

It is still another object of the present'invention to provide aspherical bearing assembly in which the annular groove is disposed onthe outer surface of the spool member and the annular rib is formedin-line annular grooves formed on the inner surface of the sphericalsegments.

Embodiments of the bearing according to the concept of the presentinvention are shown and/or de scribed by way of example in theaccompanying drawings and following description of the invention withoutattempting to show or describe all of the various forms andmodifications in which the invention might be embodied; the inventionbeing measured by the appended claims and not by the details of thespecification.

FIG. 1 is a side elevational view of the spherical bearing assemblyembodying the present invention with the longitudinal axis of the outerrace member and the inner race member being substantially coincident;

FIG. 2 is a side elevational view of the partially disassembledspherical bearing assembly embodying the present invention with thelongitudinal axis of the inner race member and the outer race memberbeing substantially perpendicular, that is, the inner race member hasbeen rotated substantially 90 in one plane;

FIG. 3 is a front elevational view of the spherical bearing assembly ofFIG. 1;

FIG. 4 is a front sectional view taken along line 44 of FIG. 1;

FIG. 5 is a front elevational view of the bearing of FIG. 2;

FIG. 6 is a front sectional view taken along line 6-6 of FIG. 2;

FIG. 7 is a perspective view of the inner race member alone in anassembled condition;

FIGS. 8a, 8b, 8c illustrate a perspective view of the component parts ofthe inner race member of FIG. 7;

FIG. 9 is a perspective sectional view of the spherical bearing of FIG.1; and

FIG. 10 is a perspective sectional view of the bearing of FIG. 2 withone of the segments of the inner race member removed.

FIG. 11 is a front sectional view of another embodiment of the presentinvention.

DESCRIPTION OFTHE INVENTION A spherical bearing embodying the concept ofthe present invention is generally indicated, as appropriate, by numeral10 on the attached drawing as set forth in FIGS. 1 through 10,inclusive.

The bearing 10 has been shown as a spherical bearing, however, thepresent invention is also directly applicable to male or female rod endtype bearings and the like.

The spherical bearing 10 comprises an outer member 12 which may beprovided with an outer cylindrical surface 14. The outer member 12 mayalso be provided with two annular faces 16. The outer member 12 isfurther provided with a concave spherical inner surface 18. It may benoted at this juncture that the outer member 12 may be similar to theouter race members as found in the prior art.

The basic thrust of the present invention is to be found in the innerrace member, hereafter referred to as the inner member which istypically formed, in the prior art, as a single solid member. The innermember as distinguished from the inner members of the prior art is acomposite member having several parts. The basic part or member is thespool member 22. The spool member 22 may be characterized as acylindrically shaped spool having an annular rib 24. The spool member 22and the annular rib 24, are so sized as to be able to be placed withinthe surface defined by the concave inner surface 18 of the outer member12. This can be best seen in FIGS. 2, 5, 6 and 10.

The spool member 22 and its various associated parts may be rotated suchthat its longitudinal axis is perpendicular to the longitudinal axis ofthe outer race member 12. There may be at least three equally sized segments 26 on the spool member 22. The segments 26 may each be providedwith an annular groove which may be formed on in-line relation so as todefine an annular groove 25 complimentary to the annular rib 24 on thespool member 22. The interlocking relationship between the groove 25 andthe annular rib 24 maintains the positional integrity, in an axialdirection, of the segments 26 on the spool member 22. However, thesegments 26 may be removed from the spool member 22when the spool memberis rotated in the above noted fashion. Each segment 26 may be moved inturn from the spool member 22 ultimately leaving the spool membercompletely devoid of the segments 26. Thereafter, the spool member canbe removed entirely from the outer member 12. It can be seen, therefore,that the inner member can be completely dismantled and removed from theouter member 12 without dislodging or otherwise interfering with theposition or the condition of the outer member with respect to itsmounting surface (not shown). This feature becomes particularlyimportant when the outer face member is fixedly attached to somestructural surface such as by press-fit or the like. For example, in anaircraft or machine tool type application, a new inner member may beinserted quickly and efficiently without disturbing any other part ofthe aircraft or machine tool except that part which is directly attachedto the inner member 20.

An additional very important feature of the present invention is thatthe inner member can be sized by varying the dimension of the convexouter surface as defined by the segments 26. By varying this dimensioncertain bearing wear, which may be experienced by the inner concavesurface of the outer member 12, can be accommodated, thereby maintainingthe overall bearing tolerance of the bearing assembly 10.

An additional very important feature of the present invention is that itinherently embodies a second or redundant bearing surface. Inparticular, the inner surfaces 28 of the segments 26 and the outersurface 30 of the spool member 22 may define a second bearing surface.This bearing surface can become particularly important in a situationwhere there may be interference between the inner member and the outermember at the bearing surface defined by the concave inner surface ofthe outer member 12 and the convex outer surface of the inner member 20.Upon any such interference, which may be caused by corrosion, dirt orthe like, the above noted second bearing surface between the sphericalsegments 26 and spool member 22 could then provide for a degree ofmovement. This movement can be further enhanced by treating the varioussurfaces with a self-lubricating plastic such aspolytetrafluoroethylene.

It is to be noted that rib 24 is depicted in the drawings as beingdisposed centrally on the outer surface of the spool member 22 while thecomplimentary annular groove 25 is disposed on the inner surface of thespherical segments. As shown in FIG. 11 the position of these elementscould, of course, be reversed the rib 29 being disposed on the innersurfaces of the spherical segments and the complimentary annular groove27 disposed on the outer surface of the spool member. The axial positionof the rib and groove could also be changed from the central position.

As before mentioned, the present invention provides a marked improvementin the ability to service spherical bearings in the field withoutdisplacing or otherwise dislodging the outer race member. This isaccomplished without any compromise in the bearing performance orcharacteristic such as a reduction in the overall bearing surface whichis typified by the prior art bearings such as the messerschmidt typeball spherical bearing.

From the above description of the invention along with various figuresas set forth in the drawings it will be readily seen and appreciatedthat a spherical bearing embodying the concept of the present inventionwill positively and effectively accomplish the objectives of theinvention. The above-noted embodiment is shown by way of example withoutattempting to show all the various forms and modifications in which theinvention might be embodied; the invention being measured by theappended claims and not the specific details of the specification.

I claim:

1. A spherical bearing assembly having an inner race member and an outerrace member, the inner surface of the outer race member being a concavespherical surface, the outer surface of the inner member being acomplimentary convex spherical surface, the inner member including aspool member having an annular rib disposed on its outer surface and atleast three axially segmented spherical segments, each segment having agroove on its inner surface complimentary to said annular rib, saidsegments disposed on and interlocked with said spool member by theregistration of said annular rib in said complimentary annular groove,each said inner member and said outer member moving at their respectivespherical bearing surfaces as a unit each with respect to the other,there being one annular rib centrally disposed on the outer surface ofsaid spool member.

2. A spherical bearing assembly in accordance with claim 1 wherein saidannular rib and said annular groove are continuous.

3. A spherical bearing assembly having an inner race member and an outerrace member, the inner surface of the outer race member being a concavespherical surface, the outer surface of the inner member being acomplimentary convex spherical surface, the inner member including aspool member having an annular groove disposed on its outer surface andat least three axially segmented spherical segments, each segment havingan annular rib on its inner surface complimentary to said annulargroove, said segments disposed on and interlocked with said spool memberby the registration of said annular rib in said complimentary annulargroove, each said inner member and said outer member moving at theirrespective spherical bearing surfaces as a unit each with respect to theother, there being one annular groove centrally disposed on the outersurface of said spool member.

1. A spherical bearing assembly having an inner race member and an outerrace member, the inner surface of the outer race member being a concavespherical surface, the outer surface of the inner member being acomplimentary convex spherical surface, the inner member including aspool member having an annular rib disposed on its outer surface and atleast three axially segmented spherical segments, each segment having agroove on its inner surface complimentary to said annular rib, saidsegments disposed on and interlocked with said spool member by theregistration of said annular rib in said complimentary annular groove,each said inner member and said outer member moving at their respectivespherical bearing surfaces as a unit each with respect to the other,there being one annular rib centrally disposed on the outer surface ofsaid spool member.
 2. A spherical bearing assembly in accordance withclaim 1 wherein said annular rib and said annular groove are continuous.3. A spherical bearing assembly having an inner race member and an outerrace member, the inner surface of the outer race member being a concavespherical surface, the outer surface of the inner member being acomplimentary convex spherical surface, thE inner member including aspool member having an annular groove disposed on its outer surface andat least three axially segmented spherical segments, each segment havingan annular rib on its inner surface complimentary to said annulargroove, said segments disposed on and interlocked with said spool memberby the registration of said annular rib in said complimentary annulargroove, each said inner member and said outer member moving at theirrespective spherical bearing surfaces as a unit each with respect to theother, there being one annular groove centrally disposed on the outersurface of said spool member.